Caroline Wozniacki, who made her pro debut eight days after her 15th birthday, doesn’t believe she will continue to play for as long as many tour veterans have, including the Williams sisters. The 24-year-old is very friendly with Serena Williams, who is 33 years old; Venus Williams, ranked No. 11, is still playing at age 34. Both have yet to decide when they will retire.

Wozniacki isn’t sure, but she can’t imagine playing for another 10 years. “No, I don’t think so,” she said. “I admire them so much for the long career they’ve had. They’ve had some tough injuries, Venus had the sickness as well and to come back and be still at the top of the game is incredible. To see what they’ve done for tennis is amazing. I don’t know.

“Serena also told me, ‘When I was your age, that’s what I said and look where I am now.’ So you don’t know, maybe in 10 years I’ll still be playing. But right now I don’t see it.”

Wozniacki is playing this week’s tournament in Dubai. The world No. 5 had a strong conclusion to last season, reaching the U.S. Open final, but has had a difficult year so far. She lost to Venus Williams in the Auckland final, retired due to injury in Sydney, and fell to Victoria Azarenka in straight sets in the second round of the Australian Open.

“I think the confidence improves with the wins you have and the players you’ve beaten. It doesn’t really matter what number is in front of your name, to me anyways,” said Wozniacki. “I was seeded high in Australia and played Victoria in the second round, seeded high here and I am playing Stosur in the second round. It’s not like it’s making a difference whether I’m seeded or not. At the end of the day it brings confidence when you win matches.”